py: Add module/function/class name to exceptions.
Exceptions know source file, line and block name.
Also tidy up some debug printing functions and provide a global
flag to enable/disable them.
diff --git a/py/emit.h b/py/emit.h
index 521b43c..309d474 100644
--- a/py/emit.h
+++ b/py/emit.h
@@ -120,7 +120,7 @@
emit_t *emit_pass1_new(qstr qstr___class__);
void emit_pass1_free(emit_t *emit);
emit_t *emit_cpython_new(uint max_num_labels);
-emit_t *emit_bc_new(qstr source_file, uint max_num_labels);
+emit_t *emit_bc_new(uint max_num_labels);
emit_t *emit_native_x64_new(uint max_num_labels);
emit_t *emit_native_thumb_new(uint max_num_labels);